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arXiv · 2111.07025

Broken mirror symmetry of tracer's trajectories in turbulence

Sofía Angriman·Pablo J. Cobelli·Mickaël Bourgoin·Sander G. Huisman·Romain Volk·Pablo D. Mininni
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Abstract

Topological properties of physical systems play a crucial role in our understanding of nature, yet their experimental determination remains elusive. We show that the mean helicity, a dynamical invariant in ideal flows, quantitatively affects trajectories of fluid elements: the linking number of Lagrangian trajectories depends on the mean helicity. Thus, a global topological invariant and a topological number of fluid trajectories become related, and we provide an empirical expression linking them. The relation shows the existence of long-term memory in the trajectories: the links can be made of the trajectory up to a given time, with particles positions in the past. This property also allows experimental measurements of mean helicity.

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Sofía Angriman, Pablo J. Cobelli, Mickaël Bourgoin, Sander G. Huisman, Romain Volk, Pablo D. Mininni. 2021-11-13. Broken mirror symmetry of tracer's trajectories in turbulence. https://doi.org/10.1103/physrevlett.127.254502

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